As a follow up to our blog about Carebundles and their general utility in Prehospital and Retrieval Medicine we thought we might go through each of the bundles that we are using in Sydney and discuss our rationale for why we included the items we did and the evidence base for them. We hope this process will provide us with some open peer review of our criteria across an international cohort of our colleagues which can only be good for us.

The first thing to note is simply a repeat of my previous post. It is hard to get good evidence in the space we work in and much of the data is extrapolated forward from in-hospital practice. Mere geography alone should not affect pathophysiology so this approach is biologically plausible but we acknowledge it is not ideal. To quote from the previous post:

“We then turned to the evidence based consensus guidelines, Cochrane reviews and good quality RCTs to define the Carebundle items. This is a sobering process as you realise just how few interventions there are that have good evidence to back them up. This is particularly true for prehospital care where we are often operating in an evidence free zone. In many cases we had no choice but to go with the consensus (or best guess as I like to call it). We decided that we would include intubation for unconscious trauma patients for example despite the evidence not being all that strong and in many cases contradictory.”

So let’s look at our bundle items for isolated severe head injury (GCS <9) and why we chose them:

Intubation and mechanical ventilation

As I have already stated the evidence here is not strong. However it certainly allows better control of both oxygenation and ventilation (PaCO2) so it makes sense and is the in-hospital standard of care. We also know that we can do this safely and extremely rapidly without delaying in-hospital care (CT scan in particular). Given we are not delaying subsequent care it seems reasonable to intubate these patients on scene given the other advantages.

Again see Davis’ papers on this subject. We are wanting low normal range (in the 35-40mmHg range) but we don’t have formal blood gases available to us in our rapid response urban operation in Sydney (we do in our longer distance transports in other parts of Australia and internationally). We therefore assume there will be a small gradient from arterial to alveolar and aimed for an ETCO2 that was likely to get our arterial level in the zone we were aiming for.

Monitoring

Our minimum is ECG, SpO2, non-invasive blood pressure and waveform, quantitative ETCO2. These are the minimum standards for managing an intubated patient in our part of the world as covered by the specialty colleges. .

Venous access

There is definitely no randomised controlled trial that shows that prehospital venous access improves outcome from severe head injury (or anything else that I know of either). However it really goes with intubation as above. We aim for pharmacologically smooth intubations without desaturation or hypotension. We need a line to achieve this.

C-spine immobilisation

Note that this does not say a rigid collar, just immobilisation which can be achieved in a number of ways. There is of course evidence that collars impede venous return and therefore it is possible they have an adverse effect mediated by effects on cerebral perfusion pressure. The consensus guidelines still cite the evidence of C spine injury associated with severe head injury so neck immobilisation made our list. We’re actively reviewing what to do when we arrive at a patient already with a rigid collar in place.

Analgesia

No evidence that I am aware of that prehospital analgesia changes outcome for patients with severe TBI, even in terms of subsequent post traumatic stress disorder in survivors. Unconscious (but not completely obtunded patients) still feel and respond to pain however. Of course it may also mitigate the risk of hypertension potentially exacerbating intracranial haemorrhage so again a biologically plausible mechanism for a benefit. I think we mainly included this one as it is what we would want for ourselves & our families.

Head elevation (External Auditory Meatus above JVP)

This is again extrapolated forward from standard in-hospital care. We need to get the brain above the effect of venous pressure to maximise cerebral perfusion. No prehospital studies on outcome (recurrent theme) but seems reasonable.

SpO2 >93%

All the large observation data sets about this quote 90% as the magic number (See Randal Chestnut and Michael Fearnside’s classic papers on this topic for example). We were simply conservative and aimed a bit higher at the inflection point of the Hb dissociation curve as desaturation occurs so rapidly below this point. I note that the Germans (ADAC) are aiming for 95% presumably due to similar thinking.

Systolic Blood Pressure >110mmHg

Again the classic papers talk about 90mmHg for this item, although if you look at the Brain Trauma Foundation guidelines, they suggest a preference for a higher target, even though they can’t say exactly where to land. Guidelines out of Italy have also recommended this sort of target previously. Again this seems to make sense from a cerebral perfusion pressure point of view.

Blood sugar level

We mandate that this be documented for all patients. Our trauma population like most other parts of the developed world is becoming older and co-morbidities are increasingly common. This one is too embarrassing to miss.

Scene time <25 mins

One fifth of patients with severe head injury have a drainable haematoma. We want to maintain a sense of urgency among our teams. Again, we recognise that there are times when circumstances stop the team achieving this. The key thing is maintaining that sense that forward momentum can be significant for the patient.

Transport direct to trauma centre

All based on observational data but taking severe trauma patients direct to designated specialist trauma centres is standard of care internationally. Even the UK have got in on the act recently.

This one is going to be controversial. Again based on beneficial effects on ICP in the ICU setting rather than hard evidence of improved outcomes. We chose hypertonic saline over mannitol as there is less electrolyte disturbance and hypotension. We are targeting the neurologically deteriorating and lateralising signs group as they may have drainable lesions and we are trying to buy time to surgical evacuation. That is the theory anyway.

This is our audit sheet that the doctors complete post mission. You will note that it contains space for the team to comment on variations from the bundle so that we can identify the reasons that we are unable to meet our management targets.

Here it is in all its documentation glory.

Although the bundle is designed for patients with GCS<9 in reality we intubate a lot of head injury patients with GCS 9-12 as well for various reasons. We do not consider application of the bundle mandatory in this group but if they do intubate the patient we encourage our teams to apply all the bundle items as well as completing an audit sheet post mission.

Did we get it right? As I said the lack of good evidence makes this process very sobering, so we would particularly welcome feedback. Next time I will have a look at our blunt multiple trauma bundle.

This post from Dr Alan Garner tackles a core problem for all practitioners who give a damn – how do you know you’re doing it well? A chat worth having and Alan has a pretty good summary of the Carebundle approach.

How do we measure quality in prehospital and retrieval medicine? Speed? Number of procedures performed? Number of twitter followers?

Seriously though, this is a question that vexed me for many years as a service director and trying to find metrics that measure things that mattered seemed an elusive task. The major part of the problem stemmed from the heterogeneity of the patient population that we treat. Even simple (but easily measured and therefore attractive to bean counters) things like timeliness are not straightforward. Not because they are hard to measure but because sometimes time matters and other times it very clearly does not. Indeed emphasising it as a measure could lead to perverse outcomes for some patients.

Let me give you a couple of examples to illustrate the problem:

Case 1. Central abdominal stab wound with hypotension.

There is almost no prehospital intervention that matters in this patient except gasoline and perhaps tranexamic acid. I don’t think anyone would argue that time is a reasonable quality measure in this patient.

Case 2. COPD patient in a small hospital an hour flying time from the nearest intensive care unit.

Patient is eventually stabilised on non-invasive ventilation after three hours of effort by the transport team at the referring site. They are then safely transported. Clearly for this patient time does not matter at all. Reporting turnaround time at the referring site in this patient may place subtle pressure on the team to intubate the patient early and depart – a move that is very clearly not in the patient’s best interests and would have placed the patient at significantly increased risk of unnecessary morbidity and mortality.

This got me thinking that our measures of quality had to be disease process specific or we were never going to move forward. Speaking with Erwin Stolpe was the turning point in my thinking.

You Should Really Try to Know Erwin

Many of you will not have heard of Erwin. Sometimes when I talk to people or read things on social media I get the impression that physician staffed HEMS started in about 2005. The reality of course is quite different. Erwin is a trauma surgeon from Munich who began flying as a resident on the Christoph 1 service out of that city in 1968 (yes, not a typo – 1968).

Here he is, at AirMed 2014 in Rome.

These days he no longer flies but is chair of the ADAC medical committee. For those unfamiliar with ADAC they run about 35 physician staffed HEMS bases in Germany and also operate several jets for longer range transports. Their HEMS services alone conduct about 50,000 prehospital cases annually. The breadth and depth of experience of this organisation is extraordinary and Erwin has been there from the beginning. You would think there might by a few pearls of wisdom there and you would be right.

The Key Cases

Erwin described to me the “tracer diagnosis” process they use to track the quality of the care that they provide. Analysis of their prehospital caseload indicated that four diagnoses made up 75% of the cases they attended. For these four diagnoses they defined the treatments that they expected the teams to achieve (see pages 52 onwards of this presentation by Erwin for more detail). They used national and international consensus guidelines as a base. They then began reporting against those criteria and they have also started to publish that performance.

What Erwin was calling “tracer diagnoses” is probably better known to us in the English speaking worlds as a “Carebundle”. Lots of people will be familiar with the ventilator Carebundle for intubated patients in the intensive care unit. Adherence to the items in the bundle is associated with lower rates of ventilator associated pneumonia. In NSW and Queensland, Health Departments have introduced bundles for central line insertion in order to tackle the rates of central line associated bacteraemia. In this case the bundle applies to a procedure or process rather than a diagnosis. Is there a place for this kind of methodology in the prehospital and retrieval world to improve quality too?

What are we talking about when it comes to PHARM?

Let’s start by looking at what a Carebundle is.

“A bundle is a structured way of improving the processes of care and patient outcomes: a small, straightforward set of evidence-based practices — generally three to five — that, when performed collectively and reliably, have been proven to improve patient outcomes.”

This definition is taken straight from the Institute for Healthcare Improvement (IHI) website. There is a bit of controversy regarding whether the items in a Carebundle really need to all be completed for the bundle to be effective in some sort of synergistic way or whether they are in fact just a checklist of items that have been shown to be effective and you get as many done as you can. I am not aware of any evidence for the synergistic effect multiplier that is implied on IHI website. I think it is unarguable however that you should try and get as many of the things that are proven to make a difference to that condition completed as possible. That is certainly the approach that we have taken.

Another quote from the IHI website describes for me what we are trying to achieve by using bundles:

“The power of a bundle comes from the body of science behind it and the method of execution: with complete consistency. It’s not that the changes in a bundle are new; they’re well established best practices, but they’re often not performed uniformly, making treatment unreliable, at times idiosyncratic. A bundle ties the changes together into a package of interventions that people know must be followed for every patient, every single time.”

Using Carebundles in hospitals is clearly not new. Even in EMS it has been previously described for benchmarking purposes. The attraction of the methodology for me was that we would know if our care for patients with severe head injury for example was following the best available evidence and we would know what proportion of our patients were receiving that care. I did not want just some of our patients to get that care, I wanted all of them to get every item of care that we could identify matters for that disease process all of the time.

Making it Match What We Do

For our rapid response service in Sydney we then determined from our medical database the diagnoses that cover 75% of our caseload as ADAC had done. For us this resulted in the following list:

Multiple blunt trauma

Isolated severe head injury (GCS<9)

Burns (>15% BSA)

Penetrating trauma

Immersion/drowning

Seizures (to which we were often being dispatched as they were mistaken for head injury or had caused a minor traumatic event)

We then turned to the evidence based consensus guidelines, Cochrane reviews and good quality RCTs to define the Carebundle items. This is a sobering process as you realise just how few interventions there are that have good evidence to back them up. This is particularly true for prehospital care where we are often operating in an evidence free zone. In many cases we had no choice but to go with the consensus (or best guess as I like to call it). We decided that we would include intubation for unconscious trauma patients for example despite the evidence not being all that strong and in many cases contradictory.

When we had defined the items for the specific diagnosis we printed them up on cards that team members carry in their pocket. These serve as a checklist which teams use on site or in transit just to be sure that they have covered all the items. Below is our isolated severe head injury card – the item I constantly forget is the blood glucose level (BSL). Highly embarrassing if this is low when you arrive at the trauma centre! I for one am glad to have the prompt.

Some of these items are extrapolated from in-hospital care. For example having the external auditory meatus (EAM) above the JVP makes sense in terms of managing raised ICP but there is no direct prehospital evidence that shows this changes outcome. We have also set relatively conservative targets for things like oximetry and blood pressure. Most of the evidence suggests SpO2 >90% is enough but we felt that desaturation happens very rapidly from this point so we would rather aim a little higher.

Aspirations and Signals

Some of the items we knew from the outset that we would never achieve in all cases. Scene time of <25mins is the obvious example. When a patient is trapped this is outside of our control. We know however that one in five patients with a severe head injury will have a drainable haematoma that is time critical. We therefore included this item in order to signal to the team that we expect them to treat severe head injury as a time critical disease in the prehospital phase.

Some of the bundles have conditional items as well. For head injury this is the hypertonic saline which we only expect to be given if there are lateralising signs or neurological deterioration.

When the team returns to base they complete an audit form indicating if the bundle items were achieved and if not, the reason for the variance. This both reinforces for our personnel the contents of the bundles and also allows us to report on compliance. Below is an example of our report for severe head injuries showing the reasons of variance in the comments section.

You can see that we don’t meet all the targets all the time, and there is usually a good reason when we don’t. However the Carebundles allow us to be transparent about what we think good care is, and also about how successful we are in achieving it. We include Carebundle compliance (along with a lot of other stuff) in our external reporting in NSW to the Ministry of Health, NSW Ambulance, The NSW Institute of Trauma and Injury Management and all the trauma centres to which we transport patients. Transparency is a key component of good governance and this processes helps us to achieve that.

Those People Were Here First

The concept is not new. I merely walk behind the giants of the industry and follow their lead in this. It is also worth noting that Russell MacDonald from Ornge in Ontario is leading a similar project with an initial group of 10 “tracer diagnoses” amongst a small international collaboration of critical care transport providers. It will be interesting to see how closely their bundle items accord with our own. Aligning our bundle items would allow us to benchmark ourselves against similar organisations in other parts of the world and create opportunities for us to learn from organisations who manage specific conditions better than we do. In the end this is about maximising the outcomes for our patients and I will gladly accept any help I can get in achieving that.

Notes:

Here’s the stuff referred to along the way, because the originals remain a vital part of looking at the issue.